Your assessment that Brazil, Russia, India aren't "superpowers destined to rule the future" misses the mark when there is a single empire which presently rules the world. BRICS represents everyone els uniting against us.
BRICS is a bloc of powerful countries aligning itself with many other less powerful countries the US empire has systematically razed and bullied, and in doing so offers the civilized world a bulwark against the brutality of America's global economic and military domination. The majority of the human beings alive on earth will be aligned with this international anti-imperial bloc. BRICS nations trading with each other, trading with OPEC nations in currencies other than the petrodollar is significant. America is going to really shit the bed in its death throes once OPEC starts selling oil for rupees, I think.